dgAlgebraMap -- Define a DG algebra map between DG algebras.

i1 : R = ZZ/101[a,b,c]/ideal{a^3+b^3+c^3,a*b*c}

o1 = R

o1 : QuotientRing

i2 : K1 = koszulComplexDGA(ideal vars R,Variable=>"Y")

o2 = {Ring => R                      }
      Underlying algebra => R[Y ..Y ]
                               1   3
      Differential => {a, b, c}

o2 : DGAlgebra

i3 : K2 = koszulComplexDGA(ideal {b,c},Variable=>"T")

o3 = {Ring => R                      }
      Underlying algebra => R[T ..T ]
                               1   2
      Differential => {b, c}

o3 : DGAlgebra

i4 : g = dgAlgebraMap(K1,K2,matrix{{Y_2,Y_3}})

o4 = map(R[Y ..Y ],R[T ..T ],{Y , Y , a, b, c})
            1   3     1   2    2   3

o4 : DGAlgebraMap

i5 : isWellDefined g

o5 = true

i6 : f = dgAlgebraMap(K2,K1,matrix{{0,T_1,T_2}})

o6 = map(R[T ..T ],R[Y ..Y ],{0, T , T , a, b, c})
            1   2     1   3       1   2

o6 : DGAlgebraMap

i7 : isWellDefined f

o7 = false